Lifestyle Intervention And The Relationship Between Plasma Visfatin And Asymmetric Dimethylarginine In Impaired Glucose Regulation

ObjectiveTo investigate the prevalence and awareness rate of impaired glucose regulation (IGR) and diabetes mellitus (DM) in Fengyutan community. To carry out lifestyle interventions to explore the management model for preventing DM which is adapt to communities and acceptable to the middle-aged and older people. To study the changes of plasma visfatin and asymmetric dimethylarginine (ADMA) levels in the subjects with different glucose tolerances, as well as analyze the relationship between plasma visfatin and ADMA.Methods1. A cross-sectional study was performed in 2192 middle-aged and elder subjects in the Fengyutan community. The participants were examined standing height, body weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), waist circumference and hip circumference and measured fasting blood glucose (FBG), total cholesterol (TC) and triglyeride (TG). Questionnaires of awareness rate of IGR, DM and hypertension were also investigated The subjects with FBG levels of 5.6mmol/L or greater were performed 75g oral glucose tolerance test (OGTT).2. The IGR subjects were measured fasting serum insulin (FINS),hemoglobin Alc (HbAlc) within a week or two, and body mass index (BMI) and waist to hip ratio (WHR), homeostasis model assessment-insulin resistance (HOMA-IR) and homeostasis model assessment-isletβ-cell function (HOMA-β) were also calculated. The intervention group was performed lifestyle interventions in the community. After one year, the intervention group and the control group were followed-up to re-examine OGTT, FINS, HbA1c, TC and TG.3. Fasting plasma visfatin and ADMA levels were measured by enzyme-linked immunosorbent assay in 26 subjects of normal glucose tolerance (NGT),32 subjects of IGR and 30 subjects of DM. Meanwhile FBG,2h Blood Glucose after glucose load (2hBG), FINS,2h Insulin after glucose load (2hINS), TC, TG, high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were measured, and standing height, body weight, SBP, DBP, waist circumference and hip circumference were examined. The atherogenic index of plasma (AIP), BMI, WHR, HOMA-IR and HOMA-P were also calculated. Furthermore we analyzed the correlation between the plasma visfatin level and other indexes.Results1. The prevalences were 11.04%for IGR,18.80%for DM,8.76%for impaired glucose tolerance (IGT) and 2.28%for impaired fasting glucose (IFG) in the FengYuTan community. The prevalences of IGR and DM increased with age before the age of 80 years and the maximum prevalences of IGR and DM were 13.70%and 21.68%in 70-to79-year age group, respectively. The prevalence of IGR was higher than that of new diabetes mellitus in every age group.2. The prevalences of IGR, IFG, IGT and DM had no significant difference between male and female populations(P>0.05).3. The prevalences of overweight, obesity and dyslipidemia were above to 50%, respectively. The prevalences of IGT, IGR and DM increased with BMI, and the maximum prevalences of those were 12.20%,14.24%and 26.78%in the obesity group, respectively. The prevalence of IGT was higher than that of IFG in every BMI group. The prevalences of IFG, IGT, IGR and DM in hypertriglyceridemia groups were higher than those in normal triglyceridemia groups. The prevalence of DM was higher than that of IGR, and the prevalence of IGR than that of IFG in every blood lipid group.4. The awareness rates of DM and hypertension were 54.85%and 67.86%, respectively. While the awareness rates of IGR was merely 2.48%. More than 50% participants had never measured blood glucose.5. We carried out lifestyle interventions in the IGR subjects for one year and 219 subjects (157 of the intervention group and 52 of the control group) were followed-up. After intervention, there were 50.32%IGT in the intervention group and 33.87%IGT in the control group who reverted to NGT(P<0.05), meanwhile 5.73%and 16.13%who progressed to DM, respectively (P<0.05). 6. After intervention, body weight, hip circumference; SBP, DBP, FBG,2hBG and HbA1c of the intervention group were all decreased compared with those of the control group (P＜0.01, P＜0.05), and FINS and HOMA-βof the intervention group were higher than those of the control group (P＜0.05). Body weight, hip circumference, BMI, SBP, DBP, FBG,2hBG, HbA1c and TG of the intervention group were all decreased compared with those at baseline (P＜0.01), and WHR, FINS and HOMA-βwere higher than those at baseline (P＜0.01, P＜0.05).7. Pearson correlation analysis showed that the decrement of FBG (AFBG) had a significant positive correlation with the decrement of body weight (AWt), the decrement of hip circumference (AHc), the decrement of DBP (ADBP) and the increment of HOMA-p (AHOMA-β)(P＜0.01, P＜0.05), and the decrement of 2hBG (A2hBG) with AWt and ADBP(P<0.01, P＜0.05), and the decrement of HbA1c(AHbA1c) with AWt and the decrement of SBP(ASBP), ADBP, the increment of FINS (AFINS) and AHOMA-β(P＜0.01). Spearman rank correlation analysis showed that AFBG had a significant positive correlation with the decrement of food per day (AFood) and the decrement of cooking-oil per month (AOil)(P＜0.05), and A2hBG with AFood, AOil and the increment of physical activity per day (AActivity)(P＜0.01, P＜0.05), and AHbA1c with AOil (P＜0.05).8. The incidence of angina attack in the intervention group was less than that in the control group(P<0.05) and we found no direct relationship between the angina attack and the physical activity.9. From the NGT, IGR to DM group, plasma visfatin and ADMA levels increased gradually. The plasma visfatin levels in the DM group were significantly higher than those in the NGT group (P＜0.01), whereas no differences were found between the IGR group and the DM group or the NGT group (P>0.05). The ADMA levels increased in the IGR group and the DM group significantly compared with the NGT group, and those in the DM group increased compared with those in the IGR group (P＜0.01).10. Pearson correlation analysis showed that the level of visfatin was positively correlated with body weight, waist circumference, BMI, WHR, FBG,2hBG, HbAlc, TG, AIP, FINS, HOMA-IR and ADMA (P＜0.01,P＜0.05), and negatively correlated with HDL-C and HOMA-β(P＜.01), but did not correlate with age, hip circumference, SBP, DBP, TC, LDL-C and 2hINS (P>0.05). 11. Multiple linear stepwise regression analysis showed that the levels of ADMA and AIP were the strongest influential factors on the plasma levels of visfatin.Conclusions1. The prevalences of IGR and DM in middle-aged and elder population have increased remarkablely in the last decade. Their health status is far from satisfaction. The community inhabitants have missed the chance that abnormal glucose tolerance may revert to normal glucose tolerance. Accordingly, it is essential that IGR screening programmes should be implementd and that intervention means be performed in the high-risk groups.2. The community-based lifestyle intervention can improve the glycemia and lipidic metabolic disturbance and pancreatic isletβ-cell function impairment, while reducing the incidence of cardiovascular events. The improvement of pancreatic isletβ-cell function may precede to that of insulin resistance in the process of abnormal glucose regulation reversal to NGT. The improvement of glycemia dysregulation accompanies with the improvement of body weitht, blood pressure, blood lipid and pancreatic islet P-cell function, and is positively correlated with lifestyle improvement.3. Visfatin is closely related with glycemia metabolism, and may one of the compensatory mechanisms to the impairment of pancreatic isletβ-cell function and the relative lack of insulin secretion in the progress of type 2 diabetes mellitus. Visfatin is also closely related with endothelial dysfunction, atherosclerosis and cardiovascular diseases, suggesting that increased levels of plasma visfatin could play a protective role to the endothelial function. Elevated blood levels of visfatin maybe one of the protective compensatory mechanisms to the endothelial function in the aggravating glycemia metabolism process. The plasma visfatin levels may act as a marker of endothelial function.